Computing Network Coordinates in the Presence of Byzantine Faults

“Computing Network Coordinates in the Presence of Byzantine Faults”
by You Zhou.
Masters thesis, MIT, (Cambridge, MA,
USA), June 2008. Also as Technical Report MIT-CSAIL-TR-2009-015.

Abstract

Network coordinate systems allow for efficient construction of large-scale
distributed systems on the Internet. Coordinates provide locality
information in a compact way, without requiring each node to contact every
potential neighbor; distances between two nodes' coordinates represent
estimates of the network latency between them.

Past work on network coordinates has assumed that all nodes in the system
behave correctly. The techniques in these systems do not behave well when
nodes are Byzantine. These Byzantine failures, wherein a faulty node can
behave arbitrarily, can make the coordinate-based distance estimates
meaningless. For example, a Byzantine node can delay responding to some
other node, thus distorting that node's computation of its own location.

We present a network coordinate system based on landmarks, reference nodes
that are used for measurements, some of which may be Byzantine faulty. It
scales linearly in the number of clients computing their coordinates and
does not require excessive network traffic to allow clients to do so. Our
results show that our system is able to compute accurate coordinates even
when some landmarks are exhibiting Byzantine faults.